Often, at the beginning of a project, it is useful to test the devices that will be used to realize the project itself.
For hard drive and compact flash it is useful to test thei performances, so we can make use of the correct (for our project) HD or CF.
To make drive benchmark test and analyze read and write performance we could use the dd program. dd is a common Unix program whose primary purpose is the low-level copying and conversion of raw data But it can be used for a lot of other purposes.
Writing performance test
localhost ~ # dd if=/dev/zero of=./file4GB.tmp bs=1M count=4096
4096+0 records in
4096+0 records out
4294967296 bytes (4.3 GB) copied, 78.191 s, 54.9 MB/s
The above command creates a file 4GB long containing only zeros. It writes 4096 times a block of data of 1 MB.
Reading performance test
localhost ~ # dd if=file4GB.tmp bs=64k | dd of=/dev/null
65536+0 records in
65536+0 records out
4294967296 bytes (4.3 GB) copied8388608+0 records in
8388608+0 records out
4294967296 bytes (4.3 GB) copied, 45.0316 s, 95.4 MB/s
, 45.0323 s, 95.4 MB/s
I'm so sorry, but the images are lost.